The Department of Natural Resources (DNR) recently reduced the statewide groundwater protection standard (GWPS) for vanadium from 0.049 mg/l to 0.007 mg/l, based on risk calculations. However, recent discussions indicate that the practical quantification level for vanadium is typically 0.050 mg/l, so in accordance with 567 Iowa Administrative Rule 137.5(9), the DNR accepts a GWPS of 0.050 mg/l.

137.5(9)Practical quantification limits. In no case will the statewide standard be less than the practical quantification limit, as determined by the department.

There may be instances where your laboratory may have difficulty reporting levels of vanadium to 0.050 mg/l. The DNR requests that such instances be evaluated case by case and discussed with the DNR.